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Note 3 - Loans Receivable and Allowance for Credit Losses - Loans (Details Textual) Pure in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) | Dec. 31, 2023 USD ($)
Assets [Abstract] |  |  |  |  |
Interest Receivable | $ 14,014,000 |  | $ 14,014,000 |  | $ 14,005,000
Financing Receivable, Unamortized Loan Cost (Fee) | (5,900,000) |  | (5,900,000) |  | (8,400,000)
Financing Receivable, Unamortized Purchase Premium (Discount) | 2,100,000 |  | 2,100,000 |  | 2,600,000
Financing Receivable, Accrued Interest, after Allowance for Credit Loss | 11,800,000 |  | 11,800,000 |  | 11,500,000
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | $ 2,494,929,000 |  | $ 2,494,929,000 |  | 2,433,015,000
Financing Receivable, Modified, Subsequent Default, Number of Contracts | 0 | 0 | 0 | 0 |
Financing Receivable, Modified, Commitment to Lend | $ 0 |  | $ 0 |  |
Financing Receivable, 90 Days or More Past Due, Still Accruing | 0 |  | 0 |  | $ 0
Financing Receivable, Nonaccrual, Interest Income | $ 41,000 | $ 55,000 | $ 244,000 | $ 164,000 |
Financing Receivable, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] | Interest Receivable |  | Interest Receivable |  | Interest Receivable
Commercial Business Portfolio Segment [Member] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | $ 312,022,000 |  | $ 312,022,000 |  | $ 255,881,000
Commercial Business Portfolio Segment [Member] | Commercial And Industrial [Member] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 296,773,000 |  | 296,773,000 |  | 238,301,000
Commercial Business Portfolio Segment [Member] | Commercial And Industrial [Member] | SBA USDA Guaranteed Certificates [Member] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 54,800,000 |  | 54,800,000 |  | 10,600,000
Asset Pledged as Collateral [Member] | Federal Home Loan Bank Advances [Member] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | 1,110,000,000 |  | 1,110,000,000 |  | 1,070,000,000.00
Asset Pledged as Collateral [Member] | Federal Home Loan Bank Advances [Member] | Federal Home Loan Bank of San Francisco [Member] |  |  |  |  |
Financing Receivable, Excluding Accrued Interest, before Allowance for Credit Loss | $ 617,900,000 |  | $ 617,900,000 |  | $ 631,100,000

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